Children and adolescents who are at high risk of future disease because of their family history are increasingly likely to be considered for participation in disease susceptibility research as greater numbers of susceptibility-conferring mutations are identified. Despite federal regulations regarding informed consent for research involving human subjects that make explicit reference to the inclusion of minors in research, no effort has been made to understand the child's perspective on benefits and harms of disease susceptibility research, and what kind of informed consent process would be meaningful to them. Moreover, little is know about whether this healthy but disease-susceptible group of children is more or less "vulnerable" than other children. This is an important group to study because (l) identifying an early predisposition to future disease might provide an opportunity to prevent the onset of disease in adulthood; and (2) there is likely to be increasing consumer interest in such testing, especially if therapeutic interventions are possible or under investigation. The proposed study will explore the process by which families at increased risk of adult-onset disease decide to involve their children in research on genetic susceptibility. Through interviews with parents at increased risk for heart disease and breast cancer, their children between the ages of l0 and l7, and the physicians they identify as influential, the investigators will explore perceptions about the motivations and barriers to participation of children in research on genetic susceptibility to these two diseases (which are perceived as different in severity and treatability). In addition to comparing two diseases, the investigators will compare families from different cultural backgrounds (African-American, Jewish and Caucasian non-Jewish) and children at different stages of cognitive development. They will conduct follow-up family interviews one year after the initial interview. They will use the results of these qualitative interviews to develop criteria (culturally and developmentally specific) for assessing the adequacy with which recommended elements of consent and assent for children's participation in disease susceptibility protocols have been addressed.